I’ve just had an email to confirm that the 13cm SG Labs transverter I ordered in May is on its way - this is good, the lead time has been exactly as specified.
Anyway, I thought I’d better get building an antenna. The DL6WU 23cm Yagi I built using K7MEM’s online calculator worked well, so I’m going down the same route.
Progress so far, all parasitic elements cut (23 of them), folded dipole and plastic pipe boom next up. I chose 24 elements because they will fit on a 1 metre boom, which is about as long as I want to carry. Estimated gain 16dBd. 2W from transverter. 80 Watts ERP at best, but I think half that should get me into OSCAR 100.
After that experiment, I’ll be looking for SOTA contacts from G/WB / GW/MW to start with (direct contacts, I’m not lugging the satellite proof-of-concept kit up a hill :o)
I still have a number of large-ish hills down in SW Scotland that I need to activate and cross off my SS-bucket list and being on them should make working you more feasible.
A quick blimp at the map suggests that Cyrn-y-Brain or The Wrekin are likely looking paths to Lamachan Hill. I had a look at Corndon Hill but that is behind the Berwyns.
As soon as you’re QRV you can start tantalising some of us up here for possible S2S QSOs. Very desirable from my view because GW is a new DXCC on 13cms for me to add to GM, G and OZ.
Cyrn-y-Brain is easily possible for me. The Wrekin would have good take off to the North, but I’ll have to check out the clag on 13cm. It is not useable for me on 23cm, too much hash from the digital TV transmitter…
I have taken 23cm to Cadaer Berwyn, which is still on my “visit” list for this year, but I’ll test out the 13cm set up before I lug it up there.
Cadair Berwyn looks very good, just Earth curvature to overcome… bit of tropo across the Irish Sea and it will be a case “My name’s Robert, I’m your father’s brother”
If we can persaude Jack to wander out to GD then there’ll be more DXCC on offer for all.
And I forgot I worked GI early in my 13cms career.
Shame Wimo don’t do a X-quad for 23cm - I have their 2m and 70cm to go up at some point - with their switch box and phasing harness can switch between H or V and L or R hand circular !!
My transverter has arrived, yea! On the bench, it puts out just over 2W with 12v supply, and just over 2.5W at 13.8v.
I had completed the Yagi the night before, and I’m chuffed to find that it has a nice low SWR at 2320MHz. I can’t quantify it exactly, but the transverter tri-colour LED is green, which represents better than 1.4:1.
On the other hand, I had overlooked the fact that the OSCAR100 satellite uplink is around 2400MHz, where the SWR is very poor eg red LED. Doh. The uplink experiment will have to wait for an alternative patch antenna to be built…
I’ll just have to make sure I get some use out of it!
Actually, it didn’t take long to make once I’d decided how to do it. The water pipe cost very little, the welding rods (one and a bit used) were given to me, and everything else was from the junk box. So, I won’t be too upset if I have to make a new one…but not yet, please
Great work. I am going to start with the 23cm transverter from SG Labs. One question on your yagi build: how to you measure the reflectors to such small fractions of a mm for cutting? For instance, 60.79mm must be hard to read on a steel ruler surely?
I mark them them slightly over size using a steel rule, cut them with a hacksaw, then file them to length. Final checking is with a vernier guage.
Using K7MEM’s calculator, he specifies the element length tolerence as “0.4mm”
I’m not sure how to interpret that, because the adjacent elements differ in length by less than 0.4mm…
I filed mine as accurately as I could, and to within less than 0.1mm. It sounds fiddly, but 3mm aluminium filler (welding) rods are very easy to handle in these sort of lengths, and behave very nicely under a file.
He says nothing about the driven element, but for this antenna, as for my 23cm version, I folded the dipole to K7MEM’s driven element length, then made a 4:1 balun using a half wavelength (x 0.66 to account for velocity factor) of semi rigid coax. I cut the coax outer to this length, with a few mm of insulation / centre conductor extending from each end.
I made my first terrestrial QSOs on 13cm during the Tuesday UKAC on 27th August, operating from the trig point of Long Mynd Pole Bank G/WB-005.
Nine contacts in about 1.5 hours, after which a heavy shower prompted me to pack up and head home as none of the gear is weatherproofed as yet.
Very interesting, and although the 24 ele yagi is very pointy, I could hear several stations each time I tuned around, and finding contacts was not too difficult. As a new band for me, I spent a fair bit of time listening.
Best DX was 308Km, I’m not sure of the propagation mode, but it was a fairly stable path and very pleasing!
I did hear one GM station calling CQ, but on the noise. I couldn’t copy the full call, and he obviously couldn’t hear me, but it was very encouraging.
Also good to have an S2S with Stewart G0LGS/P on G/CE-001
Well done Adrian, a pretty reasonable number of contacts on 13.
I was out on G/CE-004 but my 13cm failed to turn on.
only managed 3 on 3cm before the rain returned.
Perhaps work you next time.
Thanks for the S2S. Our setup is the 13cm SG Labs Transvertor in a plastic box just tie-wrapped to the back of the TP-LINK TL-ANT2424B 2.4GHz 24dBi WiFi Outdoor Grid Parabolic Antenna which is mounted on a DJ Lighting Stand.
Matt 2E0MDJ got a S2S with Stuart G1ZAR/P on G/CE-004 on 3cm.
